Cultivation and Taxonomic Classification of Wheat Landraces in the Upper Panjsher Valley of Afghanistan After 23 Years of War

After 23 years of war, current information about the biodiversity of crops in the Hindukush mountains of Afghanistan is scarce. This study aimed at assessing the genetic composition of farmers wheat (Triticum spp.) populations through a survey of 21 randomly chosen cereal fields on both sides of the Panjsher river in the upper Panjsher valley of Northern Afghanistan. A stratified sampling of wheat heads according to morphological differences was followed by estimates of field size and grain yield and a formal interview with the landowner about the cropping sequence and the inputs used. About 75% of the cereal fields were cropped in rotation systems with faba bean (Vicia faba L.), barley (Hordeum vulgare L.), potato (Solanum tuberosum L.), maize (Zea mays L.) or fallow. Manure application at between 2.3 and 5.3 t ha⁻¹ was the major source of nutrient inputs at grain yield levels between 1.2 and 4.7 t ha⁻¹. The morphological characterization of the collection revealed 19 taxonomically different varieties of bread wheat (Triticum aestivum L.) but also barley and triticale (Triticosecale Wittm.) grown in mixtures. Populations within one field consisted of up to seven botanical wheat varieties. Farmers did not differentiate between morphological differences within such mixtures but identified their populations instead according to grain color, cooking properties and resistance to mildew and frost. Triticum aestivum var. subferrugineum was the most widespread wheat variety and no effects of altitude on biodiversity of wheat was noted across the transect. Particularly interesting was the occurrence of T. aestivum var. subferrugininflatum and var. subgraecinflatum which so far have only been reported from Mongolia. The finding of triticale indicated the active seed exchange with lowland or long-distance seed sources.     

北方春大豆地方品种种子活力相关性状多样性分析

对104个北方春大豆地方品种的苗鲜重、苗高、下胚轴长、发芽率、发芽势和发芽指数等10个活力相关性状进行测定,并进行多样性分析。结果表明,大豆地方品种种子活力相关性状存在丰富的遗传变异,变异系数在17.65%~35.42%之间,其中发芽势变异系数最大,为35.42%,下胚轴长变异系数最小,为17.65%。相关性分析表明,除下胚轴长与根体积、根表面积、总根长呈显著负相关外,其余各性状之间呈显著或极显著正相关。聚类分析将104个大豆地方品种分为4个类群,类群Ⅲ的苗鲜重、苗高、下胚轴长、发芽率、发芽势、发芽指数、主根长的均值最大,类群Ⅳ总根长、根体积和根表面积的均值最大。主成分分析中前4个主成分累积贡献率达到87.854%。第1主成分反映的是大豆根系粗壮程度;第2主成分反映的是发芽速度;第3主成分反映地上部分伸长能力;第4主成分反映地下部分伸长能力。隶属函数值将104份材料按活力高低分为3类,并筛选出8个高活力地方品种（保险豆、汤原秃荚子、黄豆、宝清小金黄、和龙油太、富锦四粒黄、牛毛黄和汪清神仙洞）,可作为培育高活力大豆品种的亲本材料。     

A note about Triticum in Oman

Little is known about the diversity of wheat (Triticum spp.) in Oman. Results of a survey conducted in two remote mountain oases of northern Oman indicate that there exists considerable morphological variation within and among the five traditional landraces of wheat cultivated. Within two of the landraces grown on irrigated terraces, sized between 2 and 100 m², two new botanical wheat varieties (Triticum aestivum var. baladseetense and var. maqtaense) were identified of which the agronomic properties, in particular tolerance to drought and heat, and the nutritional value require further investigation.     

不同储藏温度和时间对长白猪肌肉pH、失水率及脂质氧化的影响

研究测定了长白猪屠宰后12h肌肉pH的下降速度、极限值和肌间脂肪氧化速度,及不同储藏温度和时间对肌肉pH值、失水率及脂质氧化的影响。结果表明:屠宰后0～5h长白猪肌肉pH值下降速度较快,9～12hTBA值变化速度较快。4℃条件下,储存时间对长白猪肌肉pH影响不显著,对滴水损失影响极显著,TBA值影响显著;-20℃冷冻条件下,储存时间对长白猪肌肉pH、TBA影响显著,对解冻失水率影响不显著。温度对pH值和TBA值的影响不明显,对滴水损失和解冻失水率有极显著的影响。通过回归分析,长白猪肌肉滴水损失和解冻失水率随pH升高而降低;-20℃条件下TBA值随pH升高而升高。     

Comparison of Fecal Methanogenic Archaeal Community Between Erhualian and Landrace Pigs Using Denaturing Gradient Gel Electrophoresis and Real-Time PCR Analysis

Erhualian and Landrace breeds are typical genetically obese and lean pigs, respectively. To compare the fecal methanogenic Archaeal community between these two pig breeds, fecal samples from different growth phase pigs were collected and used for PCR-denaturing gradient gel electrophoresis （DGGE） with two primer pairs （344fGC/519r and 519f/915rGC） and real-time PCR analysis. Results showed that a better separation and higher quality of bands pattern were obtained in DGGE proifles using primers 344fGC/519r as compared with primers 519f/915rGC. Sequencing of DGGE bands showed that the predominant methanogens in the feces of Erhualian and Landrace pigs belonged to Methanobrevibacter spp. and Methanosphaera spp. Real-time PCR analysis revealed that there was no signiifcant difference in the numbers of fecal total methanogens between Erhualian and Landrace pigs;however, pig growth phase affected the numbers of 16S rRNA genes of total methanogens and Methanobrevibacter smithii. Dissociation curves of methyl coenzyme-M reductase subunit A （mcrA） gene fragments ampliifed with real-time PCR showed all samples possessed a single peak at 82＆#176;C, which might be associated with M. smithii. Samples from the same growth phase of each breed showed good replicative dissociation curves. The results suggest that the growth phase （including diet factor） other than genotype of pig may affect the fecal methanogenic Archaeal community of pigs.     

长白仔猪采食行为的观察

对长白仔猪的采食行为进行了观察和研究。研究结果，可供长白猪的培育和饲养管理作为参考。     

蓝塘猪与长白猪正反交F_1代胴体性状和肉品质的比较

【目的】分别以蓝塘猪作为父本和母本与长白猪杂交,比较其F1代胴体和肉品质的差异.【方法】以广东地方品种蓝塘猪与外来品种长白猪为模型,采用正反交试验分别获得杂交F1代,即蓝×长猪和长×蓝猪,并采用相同日粮饲养至180日龄,比较蓝×长猪和长×蓝猪的生长性能.试验结束后每个品种分别选择接近平均体质量的8头肥育猪(公母各半),屠宰测定其胴体性状,并分析背最长肌的肉品质性状和肌球蛋白重链mRNA表达水平差异.【结果和结论】蓝×长猪和长×蓝猪的胴体性状无明显差异.但从肉品质来看,蓝×长猪的肌内脂肪含量显著高于长×蓝猪,而且公猪显著高于母猪(P0.05).蓝×长猪花生四烯酸(C20∶4)的比例显著高于长×蓝猪,但杂交后代肌纤维类型和肌苷酸含量均无显著差异.2品种和性别间MyHC-I、MyHC-IIa、MyHC-IIb和MyHC-IIx基因mRNA表达均无显著差异.由上述结果可知,以蓝塘猪为父本、长白猪为母本得到的杂交F1代肌内脂肪含量和花生四烯酸比例均较高,说明蓝×长猪可能具有更优的肉品质和营养价值.     

长白猪prepro-orexin基因多态性及其与采食和生长性状的关联分析

为揭示食欲素前体（prepro-orexin）基因对长白猪采食和生长性状的影响,试验采用PCR产物直接测序法对132头长白猪prepro-orexin基因的C62T和G426A位点多态性进行检测,并对各位点与30~100 kg阶段的采食及生长性状进行关联分析。结果表明,长白猪prepro-orexin基因C62T和G426A位点均处于Hardy-Weinberg平衡状态,等位基因频率表现为野生型（C、G）高于突变型（T、A）;两个位点的4种单倍型和7种单倍型组合中,CG、TA为主要单倍型,CG/CG、TA/CG和TA/TA为主要单倍型组合。C62T位点的CC基因型、G426A位点的GG基因型及CG/CG单倍型组合均可显著减少日采食次数、延长每次采食时间和提高每次采食量（P < 0.05）;其中CG/CG组合的日采食次数、每次采食时间、每次采食量分别较TA/CG组合显著减少1.22次、延长0.79 min和提高32.18 g（P < 0.05）,而与TA/TA组合的差异未达到显著水平（P > 0.05）。C62T位点的TT基因型、G426A位点的AA基因型及TA/TA单倍型组合可显著或极显著缩短达100 kg体重日龄、提高30~100 kg平均日增重（P < 0.05;P < 0.01）;TA/TA组合达100 kg体重日龄分别较CG/CG、TA/CG组合分别显著缩短6.23和6.69 d（P < 0.05）,平均日增重分别极显著提高47.91和50.04 g/d（P < 0.01）。结果表明,prepro-orexin基因C62T和G426A位点对长白猪采食和生长性状的影响具有明显的协同效应。     

Landraces and folk varieties: a conceptual reappraisal of terminology

Farmers’ seeds are most often lumped together in one broad category called ‘landraces’. But such a category covers variety types that reflect different levels of farmer involvement. Those differences matters when we discuss such issues as genetic erosion, on-farm conservation and seed related policies. The term landrace can be traced to the time when ‘modern’ varieties of cereals were introduced to European farmers in the late nineteenth century. The farmers’ varieties of the time were called ‘landraces’ and understood as seeds adapted to local growing conditions through natural adaptation usually with no intentional selection. But the term was quickly adopted as generic for all farmers’ varieties including those that are bred and maintained by active seed selection on-farm. Such farmer-bred varieties are better termed ‘folk varieties’. The article discusses how interaction of crop characteristics and developing technologies resulted in the evolution of crop varieties as either landraces or folk varieties. It is argued that vulnerability to different agents of genetic erosion and feasibility of on-farm conservation are clearly different for the two categories of farmers’ varieties. Likewise seed policies, particularly the issue of Farmers’ Rights would benefit from clarity of type of farmers’ varieties.     

20份玉米农家种质优势类群的划分和优势模式分析

以20份从农家种选育的自交系和6份测验种按不完全双列杂交组配120个杂交组合为试验材料,以玉米自交系总配合力效应为指标,采用类平均法进行聚类分析。结果表明,20份自交系大致可分为5大类：第1类群为铁13;第2类群为牛11、呼兰8趟、五常白头霜、呼兰老来瘪、冬黄、五常黄金塔、早大黄、宾县老来瘪;第3类群为青冈牛尾黄、五常60天还家、珍珠粟、呼兰红稂子、五常大金顶、风白12、龙江黄马牙;第4类群为木兰白头霜、大四、kl3;第5类群为克830。从组配方式看,地方种质资源与供试6大杂优类群均具有较强的杂种优势,说明地方种质资源的遗传基础比较丰富,但Lancaster×地方种质、Ried×地方种质、旅系×地方种质在利用地方种质组配出现强优势组合的概率相对较多。